Though it re-teamed Leni with The Cat and the Canary star Laura La Plante and features a similar style, The Last Warning lacks the supernatural elements of The Cat and the Canary and is therefore usually considered in the mystery genre rather than the horror genre; some historians, however, have classed it as a horror film. Elements of comedy present in Leni's The Cat and the Canary are also absent from the film. Extant published reviews of the film were varied. Mordaunt Hall of The New York Times noted the film contained "some finely directed passages," but that it was "not especially disturbing." Martin Dickstein of the Brooklyn Daily Eagle described the film as being "related with such vagueness that the picture fail[s] to hold together," but praised Leni's "propitious use of 'the camera angle,' and it is through this inventive maneuvering of the lens that the picture achieves at least a visual significance." A critic of the Los Angeles Times similarly found the cinematography "highly interesting" and the plot "lost in a maze of double and triple exposures," adding that there "is a decided lack of spontaneity in the sound sequences." The majority of the criticism surrounding the film had to do with its integration of sound. Irene Thirer of the New York Daily News, who felt the film "should never have been a talkie," elaborating that the dialogue episodes "retard the action" and "are not well done." The Montana Standard noted that the film "presents many thrills" and was widely enjoyed by the audiences at the film's premiere in Butte. A critic of the Hartford Courant alternately felt that, "as a talking picture, the film retains all the chill values of the play, with its eerie noises, screams, fright-fraught dialogue and general noise and excitement," but conceded that "it decidedly is not the scary kind of mystery play that the average person would find too startling." Sid Silverman, writing for Variety, noted the use of sound effects as "multiple, continuous, and in detail," and that the film included "enough screams to stimulate the average film mob into sticking through it." Hall also criticized the film's utilization of sound, writing: "There are too many outbursts of shrieking, merely to prove the effect of the audible screen, to cause any spine-chilling among those watching this production." The Chillicothe Constitution-Tribune noted that The Last Warning "the most thrilling mystery film released